Moved address-to-string translation code to blocks that depend on the 'verbose' flag.
[BearSSL] / T0 / TPointerExpr.cs
1 /*
2 * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining
5 * a copy of this software and associated documentation files (the
6 * "Software"), to deal in the Software without restriction, including
7 * without limitation the rights to use, copy, modify, merge, publish,
8 * distribute, sublicense, and/or sell copies of the Software, and to
9 * permit persons to whom the Software is furnished to do so, subject to
10 * the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be
13 * included in all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22 * SOFTWARE.
23 */
24
25 using System;
26
27 class TPointerExpr : TPointerBase {
28
29 string expr;
30 int min, max;
31
32 internal TPointerExpr(string expr, int min, int max)
33 {
34 this.expr = expr;
35 this.min = min;
36 this.max = max;
37 }
38
39 internal override bool ToBool(TValue vp)
40 {
41 throw new Exception("Cannot evaluate C-expr at compile time");
42 }
43
44 internal override string ToString(TValue vp)
45 {
46 return ToCExpr(vp.x);
47 }
48
49 internal string ToCExpr(int off)
50 {
51 if (off == 0) {
52 return expr;
53 } else if (off > 0) {
54 return String.Format(
55 "(uint32_t)({0}) + {1}", expr, off);
56 } else {
57 return String.Format(
58 "(uint32_t)({0}) - {1}", expr, -(long)off);
59 }
60 }
61
62 internal int GetMaxBitLength(int off)
63 {
64 long rmin = (long)min + off;
65 long rmax = (long)max + off;
66 int numBits = 1;
67 if (rmin < 0) {
68 numBits = Math.Max(numBits, BitLength(rmin));
69 }
70 if (rmax > 0) {
71 numBits = Math.Max(numBits, BitLength(rmax));
72 }
73 return Math.Min(numBits, 32);
74 }
75
76 /*
77 * Get the minimal bit length of a value. This is for a signed
78 * representation: the length includes a sign bit. Thus, the
79 * returned value will be at least 1.
80 */
81 static int BitLength(long v)
82 {
83 int num = 1;
84 if (v < 0) {
85 while (v != -1) {
86 num ++;
87 v >>= 1;
88 }
89 } else {
90 while (v != 0) {
91 num ++;
92 v >>= 1;
93 }
94 }
95 return num;
96 }
97 }